“Why should I care what happens downstream?” Why topsoil preservation matters

An example of healthy soil in Iowa (Natural Resources Conservation Service / Flickr)
An example of healthy soil in Iowa (Natural Resources Conservation Service / Flickr)
KC McGinnis | March 18, 2015

Starting tonight, Iowans will have their say on the proposed relaxing of topsoil preservation rules for newly constructed sites.

In hearings over the last year, the Iowa Department of Natural Resources has considered comments from home developers and homebuilders who wish to amend a current rule regarding topsoil conservation. While the current rule requires companies to maintain or replace at least 4 inches of topsoil on new construction sites, the industry is asking to be able to choose for themselves how much soil – if any – is to be replaced on such lots. Homeowners and conservationists have come out in defense of the current rule, which preserves soil health and prevents the headaches of flooding and runoff from land lacking in topsoil, while saving homeowners the added expense of adding the soil themselves.

At one of the initial hearings on the rule, however, a contractor is reported to have asked, “Why should I care what happens downstream?” For some, the benefits of topsoil preservation seem far off, and not worth the added $3,500-$6,000 in replacement costs per lot the industry estimates. However, all Iowans would feel the effects of relaxed soil conservation rules. Here are a few reasons topsoil matters:

  • Healthy topsoil is Iowa’s first and best defense against excessive flooding. When topsoil is removed from a lot, the land can’t hold nearly as much moisture. As a result, water from storms and snow melts simply runs off, causing increased flash flood concerns. During warm seasons, standing water on stripped land can also attract mosquitos and disease-carrying organisms.
  • In addition to moisture, land with healthy topsoil holds fertilizer better than land without it. This means that when storms come, landowners are at less risk for nutrient runoff, preventing them from incurring the added cost of applying additional fertilizers. This is also good for our rivers and streams, which are already inundated with excessive nitrates and phosphorus from nutrient runoff.
  • Healthy topsoil is an absolute necessity for growing grass, trees and gardens. Without it, homeowners will often have to haul in their own topsoil, adding unexpected costs to their home purchase which could have been folded into their mortgage in the first place (and probably at a much lower rate).
  • Topsoil protects Iowa’s water quality and reduces costs for water utilities. The Des Moines Water Works, which is suing three Iowa counties over nutrient runoff disputes, spent over half a million dollars in nutrient replacement this winter.

The Iowa DNR will hear comments regarding the proposed rule change at public hearings starting Wednesday, March 18, at the Cedar Rapids City Services Center. The DNR will also conduct hearings on March 25 in Davenport and March 27 in Des Moines. Iowans can give written comments by mail to Joe Griffin, Iowa Department of Natural Resources, 502 E. Ninth St., Des Moines, IA 50319-0034. They can also send comments by email to joe.griffin@dnr.iowa.gov .


CGRER documentary shows need for statewide flood sensor network

A still from a documentary on the development of a flood sensor network in Iowa produced by the UI Center for Global & Regional Environmental Research.
A still from a documentary on the development of a flood sensor network in Iowa produced by the UI Center for Global & Regional Environmental Research.
KC McGinnis | March 4, 2015

A new documentary produced by the University of Iowa Center for Global & Regional Environmental Research shows how one technology developed by Iowa scientists could help Iowans prepare for floods better than ever before.

The video (below) includes interviews with Iowa landowners, scientists and watershed authorities who are taking advantage of experimental flood sensors being installed in locations around northeast Iowa. The new technology, which has been under development since the 1990s, is groundbreaking in both its arrangement and scope, and has influenced similar networks across the country.

The sensors, which can be installed on farms or other land, record rainfall on the ground, rather than from radar, resulting in more accurate readings. Each sensor is actually a set of two sensors, which can help explain discrepancies in data better than single sensors. Data from these sensors is sent to the Iowa Flood Information System, an interactive website that’s free to the public, and is an important resource for landowners and municipalities during heavy rainstorms and other flood events.

Since rainfall can vary over small distances, the Iowa Flood Center is currently seeking funding to install new flood sensors in each of Iowa’s 99 counties. To see the history of the technology and to learn more, watch the video below.

UI study finds that Midwest is experiencing more serious floods

Coralville, Iowa during the Flood of 1993. (Alan Light/Flickr)
Coralville, Iowa during the Flood of 1993. (Alan Light/Flickr)

Nick Fetty | February 12, 2015

The Midwest has seen a greater number of serious floods in recent decades compared to previous years, according to a report by researchers at the University of Iowa.

“It’s not that big floods are getting bigger, but that we have been experiencing a larger number of big floods,” said Gabriele Villarini, UI assistant professor of civil and environmental engineering and a co-author of the study.

The report – which was published this week in the journal Nature Climate Change – examined 774 stream gauges in 14 Midwestern states (Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, West Virginia, and Wisconsin). The researchers concluded that 34 percent of the sensors detected an increase in flooding events between 1962 and 2011. Nine percent of the gauges showed a decrease in flood events during that same time. The region including Illinois, Iowa, Indiana, Ohio, Missouri, and North Dakota experienced the greatest increase of flood frequency.

The authors wrote: “Most of the flood peaks in the northern part of the [Central United States] tend to occur in the spring and are associated with snow melt, rain falling on frozen ground, and rain-on-snow events.” However, the report “does not attempt to pinpoint precisely how climate change might be directly responsible for these increased flooding events.”

Serious floods have inundated the region in 1993, 2008, 2011, 2013, and 2014 and have caused more than $260 billion in damages between 1980 and 2013.

Funding for this research was provided by the U.S. Army Corps of Engineers Institute for Water Resources, the Iowa Flood Center, IIHR-Hydroscience & Engineering, and the National Science Foundation.

On the Radio: Dubuque receives presidential honor for climate action

Downtown Dubuque, Iowa (SD Dirk / Flickr)
Downtown Dubuque, Iowa (SD Dirk / Flickr)
February 2, 2015

This week’s On the Radio segment looks at the environmental work of Dubuque, which was recently named a Climate Action Champion by the White House. Listen to the audio below, or continue reading for the transcript.

Transcript: Dubuque recognized by White House.

A city in Iowa was recently recognized by the White House for its efforts to address climate change.

This is the Iowa Environmental Focus.

Dubuque was named a Climate Action Champion by the White House for efforts the city has made to reduce greenhouse gas emissions, aiming to have emissions 50 percent below 2003 levels by 2030. The city is also being rewarded for its flood conscious infrastructure and flood mitigation efforts.

Dubuque – which sits along the Mississippi River – has been declared a presidential disaster zone six times in the past 16 years. Next fall the city will begin a 179-million-dollar flood mitigation project to protect some of Dubuque’s most developed and flood susceptible areas.

As a Climate Action Champion, Dubuque will be eligible for federal funding and other resources for applicable projects.

For the full list of Climate Action Champions, visit Iowa-Environmental-Focus-dot-org.

From the UI Center for Global and Regional Environmental Research, I’m Jerry Schnoor.


On the Radio: Soil conservation gains popularity among farmers

An Iowa farm in early Summer (Carl Wycoff / Flickr)
An Iowa farm in early Summer (Carl Wycoff / Flickr)
January 26, 2015

This week’s On the Radio segment looks at a recent report that shows Iowa farmers are increasingly turning to environmentally friendly soil conservation practices. Listen to the audio below, or continue reading for the transcript.

Transcript: Soil Conservation

Cover crops, crop rotation, and other soil conservation practices are gaining in popularity with Iowa farmers, according to a recent report.

This is the Iowa Environmental Focus.

The international consulting firm Datu Research released the 53-page report in December which found that 23 percent of those surveyed reported that they planted cover crops on their farms. Eighty percent of respondents said they alternate their fields between corn and soybeans each year while 70 percent of farmers said they practice minimum or conservation tilling practices.

These techniques improve soil health and help to regulate moisture content. This allows soil to retain more nitrate and phosphorus, saving farmers on fertilizer costs while also reducing nutrient runoff which is a major cause of water pollution in Iowa.

Agricultural runoff accounts for approximately 70 percent of the nitrogen and phosphorus that enters the Gulf of Mexico through the Mississippi River.

For more information about this report this IowaEnvironmentalFocus.org.

From the UI Center for Global and Regional Environmental Research, I’m Jerry Schnoor.

Dam modifications may revitalize Iowa rivers

A low-head dam in the Turkey River. (Gordon/Flickr)
A low-head dam in the Turkey River. (Gordon/Flickr)
KC McGinnis | January 7, 2015

Dam removal or modification projects may bring improved fishing and recreation to some eastern Iowa rivers.

Several projects along the Cedar, Wapsipinicon, Maquoketa and Turkey Rivers aim to repeat the success of a white-water course opened on the Cedar River in Charles City in 2011 and a rock arch rapids project opened in the Turkey River in 2010. Rock arch rapids simulate natural rapids using re-engineered or modified low-head dams, many of which have deteriorated over time and were previously not passable for aquatic life, canoes and kayaks.

In addition to becoming new destinations for kayaks and canoes, these projects also remove barriers to fish migration and improve recreational safety. The projects may prevent tragedies like a tubing accident at a low-head dam that claimed one life in the summer of 2014.

The Iowa Legislature recently increased its annual budget for small-scale dam removal and water trails to $2 million, according to a recent report in The Gazette.

Iowa Environmental Focus: Best of 2014


As 2014 comes to a close, it’s time to look at some of the Iowa Environmental Focus’s most shared and talked-about blog posts of the year. These are the posts that helped spur conversation on important environmental topics in Iowa and around the world. Thanks for your support, and Happy New Year!

Climate and health experts discuss effects of climate change on Iowans – The Iowa Environmental Focus visited the 2014 Iowa Climate Science Educators Forum in October, to learn how climate change is affecting Iowa’s air quality, water quality and public health.

Large solar energy project coming to Mitchell county in northern Iowa – This project could be one of the largest in the state, with 1,200 solar panels.

Iowa Climate Statement 2014: Impacts on the Health of Iowans – The 4th annual Iowa Climate Statement was released in October, highlighting the health effects of climate change on Iowans. The blog  took photos and video of the event, which took place at the Des Moines statehouse.

University of Iowa research examines health effects of frac sand mining – A look into the research on the health effects of frac sand mining, or fracking, in Iowa.

MIT engineers discover way to create efficient solar panels using lead recycled from car batteries – The future of solar power could lie in old car batteries, according to engineers at MIT.

Grinnell College blown off course on campus wind energy project  – The Iowa Environmental Focus covered a setback at Grinnell College, where plans for a 5.1-megawatt wind farm were halted in October.

Proposed oil pipeline would run through 17 Iowa counties – An 1,100-mile oil pipeline was proposed to run from Lyon County in the northwest corner of Iowa to Lee County in the southeast.

Ottumwa meat plant is Iowa’s top waterway polluter – A report that showed, among other concerns, that one Iowa meat plant dumped three million pounds of chemicals into the Lower Des Moines River in 2012.

Iowa’s Allamakee county looks to implement nation’s strictest fracking ordinance – In June, the Allamakee County (Iowa) Board of Supervisors voted 3-0 to approve what looks to be “the most strict frac sand mining ordinance in the nation.”

Hemp advocates announce 6th Annual Hemp History Week – This event, taking place in 2015, aims to bring attention to hemp as an environmentally sustainable crop with both nutritional and medical uses.